Pressed on who he plans to vote for if not Trump, Kirk said it wouldn’t be Hillary Clinton.

“Hillary Clinton was for the Iran agreement and I can’t support someone who is for the Iran agreement,” he said.

So who will Kirk be supporting?

“In my case, I’ll be writing in General Colin Powell [who] I think will be the best person,” he said.

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There’s a huge problem with Kirk’s rationale, however — like Clinton, former Secretary of State Powell supported the Iran agreement. He characterized it as “a pretty good deal” last fall.

Powell praised the steps Iran took to reduce their ability to build nuclear weapons. “These are remarkable changes, and so we have stopped this highway race that they were going down — and I think that’s very, very important,” Powell said in September.

Duckworth’s campaign seized on Kirk’s inconsistency. A statement attributed to Duckworth spokesman Matt McGrath said Kirk “can’t keep his facts straight and doesn’t know that he’s talking about. In the era of Trump, deciding who should be the next President is serious business, and this is deeply unserious from Senator Kirk.”

Kirk may have to look for another Republican name to write in, but write-in campaigns are becoming more popular among the #NeverTrump contingent. Sen. Susan Collins (R-ME) suggested she might cast a write-in vote for Jeb Bush on Tuesday, a day after she wrote an op-ed for the Washington Post arguing that Trump “does not reflect historical Republican values nor the inclusive approach to governing that is critical to healing the divisions in our country.”